Nationality: United StatesExecutive summary: Physicist at University of Chicago

American physicist Leona Woods (sometimes cited as Leona Marshall or Leona Libby) graduated from high school at 14 and earned her degree in physics from the University of Chicago when she was 18. She studied under Enrico Fermi and Robert S. Mulliken, and was the only woman among the fifty members of Fermi's "Pile One" team that built the world's first artificial nuclear reactor. She was the most accomplished scientist among the handful of women who worked on the Manhattan Project, selected due to her expertise in the physics and mechanisms necessary for creating vacuums needed for boron trifluoride counters, which in turn are necessary for measuring neutrons and creating a nuclear chain reaction. She oversaw design and construction of the project's neutron detectors, and was present for the first nuclear chain reaction on 2 December 1942 at the University of Chicago.

In her long career she studied climatology, diatomic molecular spectroscopy, fundamental particle physics, the general structure and evolution of the universe, quantum chemistry, and quasars. She was an outspoken advocate of nuclear power, and maintained that its safety was supported by the birth of her two healthy children from pregnancies while she was working intimately with nuclear reactors. Her first husband, physicist John Marshall Jr, was a physicist at the University of Chicago and a great-great-great-grandson of US Supreme Court Justice John Marshall. Her second husband, Willard F. Libby, won the Nobel Prize in 1960 for his development of the carbon-14 dating technique.